The NPI status was 1st published about 1992 as an
attempt at using some fairly objective parameters to determine the odds that a newly
diagnosed case of invasive ductal adenocarcinoma would benefit from adjuvant chemotherapy. By
whatever means, the status of the axillary lymph nodes must be determined at least as to
whether any nodes are positive for metastatic cancer (ALN+) or negative (ALN-). If any
positive nodes, more details are needed. The studies looked at "overall survival" (OS) at 15
years post diagnosis. This grouping is just an initial categorization; many other
patient-specific factors are taken together to make a final decision.

SIZE:Decisions may have to be
made prior to having the whole tumor out and size-measurable. By whatever measure, the following
are the criteria for assignment of size points (such are finally, ultimately, assigned from the
pathology tissue studies):